The Effects of Ausforming on Variant Selection of Martensite in Cr-Mo Steel

• Shigeta Tomoharu

  Graduate, school of Engineering Osaka University

• Takada Atsushi

  Graduate, school of Engineering Osaka University

• Terasaki Hidenori

  Joining and Welding Research Institute Osaka University

• Komizo Yu-ich

  Joining and Welding Research Institute Osaka University

Abstract

The effects of ausforming on variant selection of martensite in Cr-Mo steel were investigated. The non-ausformed martensite and martensite ausformed at 850°C and 750°C were analyzed. Blocks were elongated in a single direction in the non-ausformed martensite specimens, however, blocks were elongated in multiple directions in ausformed martensite specimens. EBSD analyses indicated that non-ausformed martensite specimens contained only a single packet in a single γ, but that ausformed martensite specimens contained four packets in a single γ. The sizes of the blocks and packets decreased with ausforming. In situ observations revealed that blocks were formed only from γ grain boundaries in non-ausformed martensite specimens. In contrast, in the ausformed γ grains, sub-grain boundaries were observed, and martensite blocks were formed from γ grain boundaries as well as sub-grain boundaries. The blocks were not developed parallel to the slip band. The elongation of the blocks was stopped at sub-grain boundaries; as a result, packet size was considered to be smaller.

Journal

• QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY

  QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY 31 (4), 178s-182s, 2013

  JAPAN WELDING SOCIETY

Keywords

• Martensite
• In situ Observation
• Ausforming
• Variant Selection
• EBSD

Details

• CRID: 1390001204725861248
• NII Article ID: 130004445758
• DOI: 10.2207/qjjws.31.178s
• COI: 1:CAS:528:DC%2BC3sXhslejs7bL
• ISSN: 24348252
• ISSN: 02884771
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed